WTF? FRR for BTC is only 0.0155% daily. That's about 5% per year after fees.
Look at the bright side, its very cheap to short bitcoins! and we are in a down trend...
Considering that bitcoin inflation is still about 10% per year, you are indeed paying a negative real interest for them. It would be interesting if you could then withdraw the BTC that you short on Bitfinex.
Quite sure swap providers wouldn't find it too funny

Um, well. Now we are talking about Bitcoin inflation. One of the major arguments for Bitcoin was the absence of inflation. Now where this beast (the inflation) came to this movie without me noticing it?
As long as money supply increases, there's inflation. And right now we are still having about 10% yearly inflation. Take a look at the following charts:
https://bitcointalk.org/index.php?topic=130619.0In some years, inflation will be so low that it'll be irrelevant, but for the moment it's still something considerable.